The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Jan. 14, 1997
Filed:
Dec. 29, 1994
Chul-woo Lee, Seoul, KR;
Kyung-hwa Rim, Seoul, KR;
Pyong-yong Seong, Seoul, KR;
Chong-sam Chung, Sungnam, KR;
Samsung Electronics Co., Ltd., Suwon, KR;
Abstract
In an optical pickup, a focus error detector for detecting a focus error of an objective lens for an optical disk includes a focusing lens for focusing the reflected light of the optical disk, a diffraction optical device for diffracting the reflected light focused by the focusing lens into two light rays, two bi-segmented photo-detectors for receiving the two split light rays, respectively, and a circuit for outputting a desired focus error signal from the signal detected from the photo-detectors. The circuit outputs a pure focus error signal without errors created by the deviation of the light amount in the photo-detectors due to the tilt or shift of the reflected light, thereby contributing to the stable operation and miniaturization of the optical pickup.